1. Moon Phases, and Eclipses

2. Motions of the Moon
Moon revolves around the Earth and rotates on its axis.
Takes 27.3 days to revolve around Earth.
Rotates slowly on its axis, once every 27.3 days.
Earth only sees the same side of the moon.
“Far side” always faces away.

3. Phases of the Moon
We see the moon because it reflects light from the sun.
The moon’s shape changes during the month causing the phases.
Moon Menu

4. Phases of the Moon New Moon
The sun lights the side of the moon facing away from Earth. This side of the moon that faces the Earth is dark.
Moon Menu

5. Phases of the Moon Waxing Crescent
You see more and more of the lighted side of the moon.
Moon Menu

6. Phases of the Moon First Quarter
You see half of the lighted side of the moon.
The moon is ¼ of the way through it’s orbit.
Moon Menu

7. Phases of the Moon Waxing Gibbous The moon continues to wax.
The moon is called a waxing gibbous.
Moon Menu

8. Phases of the Moon Full Moon
The whole lit side of the moon can be seen from Earth.
This is known as a Full Moon.
Moon Menu

9. Phases of the Moon Waning Gibbous
The Moon now becomes darker each day. This is known as a waning gibbous
Moon Menu

10. Phases of the Moon Third Quarter Moon
You can see half of the moon’s lit side. The moon is ¾ of the way through it’s orbit. This is called a third quarter moon, or last quarter moon.
Moon Menu

11. Phases of the Moon Waning Crescent The last phase before new moon.
Moon Menu

12. Phases B F H A
Cause C I E D
Eclipses

13. Phases of the Moon
Phases are caused by changes in the relative positions of the moon, Earth and sun.
As the moon revolves around the Earth, we see the moon from different angles.
The phase of the moon depends on how much of the sunlit side of the moon faces Earth.
Moon Menu

14. Phases of the Moon The cycle begins at new moon.
The amount of light on the moon will gradually increase (Waxing) to full moon.
After full moon, the light will gradually decrease (Waning) back to new moon.
Moon Menu

15. Phases of the Moon One lunar cycle lasts 29.5 days.
Objective: I will be able to describe how the Moon moves and what causes the phases.
Phases of the Moon
One lunar cycle lasts 29.5 days.
Moon Menu

16. Eclipses The moon’s orbit is slightly tilted. As a result, the
moon doesn’t always pass into the Earth’s shadow or the shadow from the moon isn’t cast on the Earth.
Moon Menu

17. Eclipses
When the moon’s shadow hits the Earth or the Earth’s shadow hits the moon, an eclipse occurs.
An eclipse occurs when an object in space comes between the sun and a third object and casts a shadow on that object.
Moon Menu

18. Solar Eclipse
Occurs when the moon is in the new moon phase and it passes between the Earth and the sun.
Blocking sunlight from the Earth.
The moon’s shadow hits the Earth.
Moon Menu

19. Total Solar Eclipse
Occurs when the darkest part of the moon’s shadow, “the umbra” hits the Earth.
Sunlight is completely blocked in any part of this shadow.
Must be in the shadow of the umbra to see a total solar eclipse.
Stars, and the corona are visible.
Moon Menu

20. Partial Solar Eclipse
Occurs when the less dark shadow “the penumbra” hits Earth.
People in the penumbra only see a partial eclipse.
Part of the sun is still visible.
It is not safe to look directly at the sun.
Moon Menu

21. Lunar Eclipse
Occurs at a full moon when the Earth is directly between the moon and the sun.
Earth blocks sunlight from reaching the moon.
The moon is in the shadow and looks dark.
Can only occur during a full moon.
Moon Menu

22. Total Lunar Eclipse Occurs when the moon is in the Earth’s “umbra”
The dark shadow.
Can be seen anywhere on the dark side of the Earth where the moon is visible.
More likely to see a lunar eclipse than a solar eclipse.
Moon Menu

23. Partial Lunar Eclipse
Occurs if the Earth, moon and sun are not quite in a line.
The moon only partially passes into the umbra of the Earth’s shadow.
Edge of shadow appears blurry.
Last up to 2 or 3 hours.
Moon Menu